The effects of costly telomere maintenance on lifespan - reproductive tradeoffs in sand lizards.

Telomeres are DNA-protein structures that primarily protect chromosomes and serve multiple functions of gene regulation. When cells divide, telomeres shorten and their main repair system in ectotherms - telomerase - replaces lost nucleotide complexes ((T2AG3)n in vertebrates). It remains a challenge to experimentally investigate resource requirements for telomere maintenance and its effects on lifespan-reproductive tradeoffs in the wild.

Inbreeding effects on telomeres in hatchling sand lizards (Lacerta agilis): An optimal family affair?

Telomeres are nucleotide-protein caps, predominantly at the ends of Metazoan linear chromosomes, showing complex dynamics with regard to their lengthening and shortening through life. Their complexity has entertained the idea that net telomere length and attrition could be valuable biomarkers of phenotypic and genetic quality of their bearer. Intuitively, those individuals could be more heterozygous and, hence, less inbred.

Exercise training has morph-specific effects on telomere, body condition and growth dynamics in a color-polymorphic lizard.

Alternative reproductive tactics (ARTs) are correlated suites of sexually selected traits that are likely to impose differential physiological costs on different individuals. While moderate activity might be beneficial, animals living in the wild often work at the margins of their resources and performance limits. Individuals using ARTs may have divergent capacities for activity.

Stress-related changes in leukocyte profiles and telomere shortening in the shortest-lived tetrapod, Furcifer labordi.

Background: Life history theory predicts that during the lifespan of an organism, resources are allocated to either growth, somatic maintenance or reproduction. Resource allocation trade-offs determine the evolution and ecology of different life history strategies and define an organisms' position along a fast-slow continuum in interspecific comparisons. Labord's chameleon (Furcifer labordi) from the seasonal dry forests of Madagascar is the tetrapod species with the shortest reported lifespan (4-9 months).

Contrasting seasonal patterns of telomere dynamics in response to environmental conditions in the ectothermic sand lizard, Lacerta agilis.

Telomeres, the protective, terminal parts of the chromosomes erode during cell division and as a result of oxidative damage by reactive oxygen species (ROS). Ectotherms rely on the ambient temperature for maintaining temperature-dependent metabolic rate, regulated through behavioural thermoregulation. Their temperature-dependant metabolism, hence also the ROS production, is indirectly regulated through thermoregulation.